Accelerated Co-Growth of galaxies and SMBHs in a z = 3 Proto-Cluster

We present results from a series of ALMA and JWST observations targeting the SSA22 proto-cluster at z = 3.1. At the core of the proto-cluster, we identify about 20 dusty star-forming galaxies (DSFGs) embedded within extended Lyman-alpha filaments stretching over 4 comoving Mpc. By combining these data with X-ray observations and JWST/MIRI F2100W imaging, we find that the brightest DSFGs frequently host obscured AGNs—many of which had remained undetected for years. The striking overabundance of both DSFGs and AGNs in this specific environment suggests that the co-evolution of galaxies and supermassive black holes is being accelerated simultaneously along the gas filaments of the cosmic web. High-resolution imaging with ALMA and JWST (resolving down to 350 pc at 1.1 mm) reveals that many DSFGs show disk-like morphologies with embedded spheroidal components in both dust and stellar emission. Several sources harbor compact, luminous dusty cores that likely trace the sites of active bulge and black hole growth. Notably, the brightest DSFG—identified as a massive spiral galaxy hosting an obscured AGN—shows gas flows along dust lanes within a bar connected to a bright dusty core. The estimated bulge-to-SMBH mass ratio aligns with the local bulge mass-SMBH mass relation, suggesting that bar-driven inflows play a crucial role in shaping the early co-evolution of bulges and supermassive black holes.